Authors: J.A. Darnell, Steven Tomczyk, Gregory Card, Phillip Judge, Roberto
Casini, Joan Burkepile
Affiliation: National Center for Atmospheric Research, High Altitude Observatory
The Coronal Multi-channel Polarimeter (CoMP) is a filter-based polarimeter designed to provide quantitative measurements of magnetic fields in the solar corona. It will measure the Stokes parameters at the 1074.7 and 1079.8 FeXIII coronal emission lines, and the 1083.0 nm HeI chromospheric line. The CoMP is based on a four stage birefringent filter and is designed such that two polarization states at two wavelengths are imaged simultaneously. The strength of the line-of-sight component of the coronal magnetic field is inferred from the measured amplitude of the Stokes V profile and an estimate of the plane-of-sky direction is made from the Stokes U/Q ratio. Further, inference of line-of-sight velocities can be made from Stokes I (red and blue wing) amplitudes. Finally, it may be possible to obtain a coronal density diagnostic capability from the ratio of the 1074.7/1079.8 amplitudes. The CoMP was deployed in February, 2004 at the Hilltop Dome at Sac Peak and observations will be started during subsequent trips. Any preliminary data obtained by the meeting will be presented.